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1.
利用力学与电学性能测试、透射电子显微镜(TEM)对Cu-9.0Ni-1.4Al合金的时效过程进行了观察和研究;分析了Cu-9.0Ni-1.4Al-0.5Ti合金的组织和性能,分别比较了Cu-9.0Ni-1.4Al和Cu-9.0Ni-1.4Al-0.5Ti合金在3种形变热处理工艺下的力学和电学性能.性能试验结果表明:Ti的加入能够提高合金的硬度,而对导电率影响不大,经过工艺3试验后,Cu-9.0Ni-1.4Al和Cu-9.0Ni-1.4Al-0.5Ti合金的维氏硬度分别达到243、317,导电率分别达到19.1%IACS、21.0%IACS.TEM观察结果表明:Cu-9.0Ni-1.4Al合金时效过程中的主要强化过程是γ'相(Ni3Al)的连续沉淀.  相似文献   

2.
通过中频熔炼—铁模铸造—热轧—固溶处理—冷轧—时效处理工艺制备了Cu-0.5Cr-2Ni合金板材。采用拉伸力学性能测试、电导率测试、金相和透射电子显微镜观察研究了不同时效处理对该合金组织和性能的影响。结果表明,Cu-0.5Cr-2Ni合金在固溶处理为930℃×1 h、冷变形量为60%、时效状态为450℃×4 h的条件下综合性能最好。该合金的抗拉强度、屈服强度、伸长率、电导率分别达到438 MPa、398 MPa、12.4%、45.5%IACS。  相似文献   

3.
通过对不同Ag含量的Cu-15Ni-8Sn合金铸态、固溶态和时效态的微观组织进行分析,研究了Ag添加对 Cu-15Ni-8Sn 合金组织及性能的影响。结果表明,适量Ag元素的添加能够减少铸态Cu-15Ni-8Sn合金 的枝晶间距,抑制显微偏析,改善合金的铸态组织。此外,当Ag含量为0.2 wt.%~ 0.5 wt.% 时,可有效抑制时效过程中不连续沉淀相的析出,从而改善合金的力学性能。但是,当Ag添加量大于等于0.5 wt.% 时,对不连续沉淀的抑制效果减弱。  相似文献   

4.
采用显微硬度、电导率、光学显微镜(OM)和透射电子显微镜(TEM)等测试手段,研究了不同淬火方式对Cu-1.5Ni-0.34Si合金组织与性能的影响。结果表明:采用终轧温度为650℃的热轧在线淬火方式,可获得较高过饱和固溶度的Cu-1.5Ni-0.34Si合金。经该处理后的合金,时效后可以获得与800℃固溶处理后时效相当的综合性能,显微硬度(HV)可达180,电导率可达50%IACS。  相似文献   

5.
通过光学显微镜、维氏硬度计、涡流电导仪、X射线衍射仪、透射电子显微镜等仪器设备对Cu-6.0Ni-1.4Si-0.15Mg-0.1Cr合金的组织结构和性能进行了表征与测试.结果表明:合金铸态组织为发达的树枝晶组织,并可分为白亮的枝晶区、灰色的中间过渡区及非平衡凝固相粒子.非平衡凝固相主要为δ-Ni2Si和β-Ni3Si.合金主要的强化机制为时效析出强化,主要强化相为δ-Ni2Si.合金经过适当的形变热处理后,硬度为353 HV,抗拉强度为1 010 MPa,屈服强度为930 MPa,伸长率为3.8%,电导率为29.7%IACS.  相似文献   

6.
研究了以Fe-2Ni为基体,向其中分别加入0.5%、1%和3%的Cr时,合金烧结态和热处理态的力学性能和微观组织变化。结果表明,随着Cr含量的增加,合金密度降低,孔隙增多且变大;烧结态强度和硬度增加,伸长率和冲击吸收功下降。Fe-2Ni-3Cr合金的强度和硬度最高分别为975MPa和73.3HRB;Fe-2Ni合金的伸长率和冲击吸收功最高分别为12%和7.6J;热处理态合金强度相差不大,Fe-2Ni-0.5Cr的强度最高达到1240MPa;伸长率和冲击功下降;硬度增加。烧结态合金的微观组织为珠光体+很少量的铁素体,Fe-2Ni-3Cr合金中出现Ni的富集区;热处理态合金的微观组织加入Cr后变为回火马氏体,且在Fe-2Ni-3Cr合金中出现网状的二次渗碳体。  相似文献   

7.
对Cu-Ni-Al系合金的铸态组织进行研究,使企业更好地认识和了解Cu-Ni-Al系列合金,进而更好地开发利用该合金.采用金相显微镜、扫描电子显微镜和能谱仪,对Cu-Ni-Al和Cu-Ni-AlTi合金进行观察和分析.结果表明:Cu-9.0Ni-1.4Al合金铸态组织中枝晶组织与偏析区(Ni3Al)界限十分明显,且枝晶组织比较粗大.而Ti的加入促使Ni和Cu的分布变得均匀,并且Ti的加入使合金中有魏氏体产生,致使合金的力学性能降低,减小了合金的变形能力,导致Cu-9.0Ni-1.4Al-0.5Ti合金在热轧时有开裂的现象发生.并且能谱分析显示Ni3Al存在于枝晶中和枝晶间,说明Ni3Ti的稳定性较好,在高温时就有Al3Ti形成,在固溶扩散过程中,Ni3Ti被排挤到枝晶之间,形成第二相.  相似文献   

8.
采用大气熔铸工艺制备不同Co含量的Cu-0.2Be-XCo合金(X=0、0.5%、1.0%,质量分数),采用维氏硬度计、金属电导率测试仪及金相显微镜对合金的性能及组织进行测试.结果表明:随着Co含量的增加,铸态Cu-0.2Be-XCo合金的中心等轴晶区域逐渐扩大、粗大柱状晶区域减小,晶粒明显细化;Co的添加提高了铸态合金硬度,但同时降低了导电率,Cu-0.2Be-1.0Co合金的硬度较Cu-0.2Be合金增加23.5%,而导电率降低39.9%.合金经950℃×1 h固溶+460℃不同时间时效后,Cu-0.2Be合金导电率及硬度随时效时间基本不发生变化,Cu-0.2Be-0.5Co合金及Cu-0.2Be-1.0Co合金导电率及硬度在时效初期(0~2 h)急剧升高,中期(2~4 h)缓慢增加,后期(4~8h)趋于稳定.时效态Cu-0.2Be-0.5Co合金的综合性能较佳,经460℃×2 h时效,导电率为57.1%IACS,硬度(HV)为243.  相似文献   

9.
对Cu-0.70Cr-0.15In合金在形变热处理过程中的显微组织及电导率、抗拉强度等演变规律进行了研究。合金铸态组织中,在α相周围不连续分布着(α+Cr)共晶体,In均匀分布于α基体相中;合金在低于500℃时效,依然能清晰保持着时效前冷变形组织形貌,550℃时效120 min后可观察到少量的再结晶组织。结果表明,在经过1000℃×60 min的固溶处理及应变ε为80%的冷变形工艺后,合金在450℃×60min时效后具有最优的电导率和抗拉强度综合性能,其电导率和抗拉强度分别达到81.41%IACS和544 MPa,延伸率δ为13%。合金时效后再经过45%的冷变形,其抗拉强度得到迅速提升,达到641 MPa,电导率和延伸率分别仍可维持在81.2%IACS和4.5%。软化温度测试结果表明,合金时效态和"时效+冷变形"态的软化温度分别为525和440℃。  相似文献   

10.
Al-4.8Cu-0.5Mg-0.3Ag-0.15Zr合金固溶工艺的研究   总被引:2,自引:1,他引:1  
采用光学显微镜(OM)、差示扫描量热法(DSC)、扫描电镜(SEM)和X射线衍射(XRD)等分析手段,以及通过力学性能和电导率测试验证,研究J,新型Al-4.8Cu-0.5Mg-0.3 Ag-0.15Zr合金挤压板带的固溶工艺,研究结果表明:(520~525)℃×(1.5~2)h是较适合该合金的单级固溶工艺,材料在该固溶制度下进行160℃×24 h时效后能够获得515~526 MPa的室温抗拉强度和14%~15%的伸长率,以及41.7%IACS的电导率.  相似文献   

11.
Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.  相似文献   

13.
鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".  相似文献   

14.
张兴强  叶运福 《冶金设备》2005,(6):71-72,47
针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。  相似文献   

15.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。  相似文献   

16.
In this paper is treated the fundamental problematic of the fracture of the diaphysis of the tibia and the therapeutic results after the conservative and operative treatment are confronted. Among 518 patients with 433 open fractures and 35 with closed fractures of the diaphysis of the tibia, successful treatment of more 2/3 was obtained in the period from 1968 to 1972. Following our casuistics and literature, whose results are similar, we find out that the average total treatment of the osteosynthesis of the fracture of the diaphysis was shortened for 2,5 months depending upon the type and the localisation of the fracture. Apolied methods of the operative and conservative and conservative treatment in relation to the velocity of the medical cure as well as to the extreme anatomical-functional results are analised. We noticed that osteosynthesis, made by the intermedullary nail and the extension of the canals or by a small AO table, by the achieved stability makes conditions of immediate motions and an early rehabilitation. Because of that it gives the best functional results.  相似文献   

17.
18.
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.  相似文献   

19.
通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。  相似文献   

20.
为了编制实用性强的基地建设行动方案,首先,确定参与式发展的主体,搭建一个"决策框架";其次,针对行动目标,提出不同参与主体,如管理者、农民、消费者等团队与个人的目标及行动内容;最后,工作应向重塑伙伴式合作关系,挖掘农民自我发展潜力,完成三大角色的转换,打造农业基地文化等方向推进.  相似文献   

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